Flow medium monitoring device

Abstract

The flow medium monitoring device of the present invention includes: a light source part for irradiating light; a first collimator part for collimating the light irradiated by the light source part; a flow pool part in which the flow medium flows and allows the light to travel along the travel direction of the flow medium while absorbing the wavelength of the flow medium; and a light detection part for detecting the wavelength of light passing through the flow pool part.

Description

Technical Field

[0001] The present invention relates to a flowing medium monitoring device, and more particularly, to a flowing medium monitoring device capable of accurately monitoring the state of a flowing medium under the use conditions of the flowing medium. Background Art

[0002] Generally speaking, in a semiconductor manufacturing process such as a semiconductor wafer or a photovoltaic cell, an etching process is performed. In the etching process, a high-temperature etching solution (flowing medium) such as a phosphoric acid solution is used to etch a silicon nitride film. Since a dissolution such as silicon in the semiconductor wafer is dissolved and included in the etching solution, the concentration of the dissolution in the etching solution increases as the semiconductor wafer etching process proceeds. If the concentration of the dissolution in the etching solution increases to a fixed concentration or more, the etching solution is replaced.

[0003] Since it is difficult to micro-analyze the concentration of silicon in the etching solution at high temperature, a portion of the etching solution is collected and cooled to room temperature. In order to increase the detection sensitivity of the cooled etching solution, the concentration of the etching solution is detected after performing chemical treatment multiple times.

[0004] However, in the past, multiple chemical treatments were performed after the etching solution was cooled to room temperature, so the detection error range increased with the temperature difference of the etching solution. Therefore, it is difficult to accurately predict the state of the etching solution under the conditions used in actual semiconductor manufacturing processes.

[0005] Furthermore, when a high-temperature etching solution is cooled to room temperature, an eluting substance is likely to precipitate from the etching solution, and thus it is difficult to accurately measure the concentration of the eluting substance in the etching solution.

[0006] In addition, in order to accurately measure the concentration of the etching solution, it undergoes multiple chemical treatments, which makes the matrix in the concentration analysis complicated and reduces the accuracy of the concentration analysis.

[0007] The background technology of the present invention is disclosed in Korean Patent Gazette No. 1785859 (authorized on September 29, 2017, invention name: fluorescent silicon nanoparticles for copper ion detection, its manufacturing method and detection sensor using the same). Summary of the invention

[0008] Technical issues to be solved

[0009] According to one embodiment of the present invention, there is provided a flowing medium monitoring device capable of accurately monitoring the state of a flowing medium under the use conditions of the flowing medium.

[0010] Solutions to technical problems

[0011] The flow medium monitoring device of the present invention comprises: a light source part, which irradiates light; a first collimator part, which collimates the light irradiated by the light source part; a flow pool part, in which the flow medium flows and allows the light to travel along the travel direction of the flow medium while absorbing the wavelength of the flow medium; and a light detection part, which detects the wavelength of the light passing through the flow pool part.

[0012] The light detection section may include: a second collimator section that condenses the light that has passed through the flow cell section; and a light detection unit section that detects a wavelength of the light that has passed through the second collimator section.

[0013] The light source unit may include a light emitting lamp configured to radiate light, and a convex lens unit configured to focus the light radiated by the light emitting lamp.

[0014] The first collimator unit may collimate the angle of light incident from the light source unit at a fixed angle.

[0015] The second collimator section may focus parallel light that has passed through the flow cell section on the light detection unit section.

[0016] The flowing medium monitoring device may further include a noise reducing unit installed on the light detecting unit to cool the light detecting unit.

[0017] The flow medium monitoring device may further include: a slit portion, which allows the light irradiated from the second collimator portion to pass through and causes the light to be diffracted; and a wavelength selection portion, which is arranged between the slit portion and the light detection unit portion and causes the light incident from the slit portion to be split into the light detection unit portion.

[0018] The flowing medium monitoring device may further include a detection wavelength adjustment unit configured to adjust a wavelength of light irradiated to the light detection unit as the wavelength selection unit is rotated.

[0019] The flowing medium monitoring device may further include a wavelength selection unit that is disposed between the light source unit and the first collimator unit and splits the light incident from the light source unit.

[0020] The flowing medium monitoring device may further include a first optical fiber portion connected to the light source portion and the first collimator portion, and the first optical fiber portion forms an optical path so that the light irradiated from the light source portion irradiates the first collimator portion.

[0021] The flowing medium monitoring device may further include a second optical fiber portion, the second optical fiber portion forming an optical path so that the light irradiated through the flow cell portion is irradiated to the light detection unit portion.

[0022] Effects of the Invention

[0023] According to the present invention, light travels along the traveling direction of the flowing medium in the flow cell portion, so that scattering and refraction caused by bubbles or dissolved substances when light passes through the flowing medium can be minimized and light loss can be reduced.

[0024] In addition, according to the present invention, a high-temperature flowing medium flows into the flow pool portion and light is irradiated to the flowing medium, thereby eliminating the need to chemically treat the flowing medium multiple times to measure the concentration of the flowing medium under conditions used in actual semiconductor processes and to increase the detection sensitivity of the flowing medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 FIG. 1 is a diagram showing the structure of a flowing medium monitoring device according to a first embodiment of the present invention.

[0026] Figure 2 FIG. 2 is a diagram showing the structure of a flowing medium monitoring device according to a second embodiment of the present invention.

[0027] Figure 3 FIG. 1 is a diagram showing the structure of a flowing medium monitoring device according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following is an explanation of an embodiment of the flow medium monitoring device of the present invention with reference to the accompanying drawings. In the process of explaining the flow medium monitoring device, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for the sake of clarity and convenience. In addition, the terms described below are defined in consideration of the functions in the present invention, and they may vary depending on the intention or practice of the user or operator. Therefore, the definition of such terms should be made based on the content of the entire specification.

[0029] First, a flowing medium monitoring device according to a first embodiment of the present invention will be described.

[0030] Figure 1 FIG. 1 is a diagram showing the structure of a flowing medium monitoring device according to a first embodiment of the present invention.

[0031] If reference Figure 1 The flowing medium monitoring device according to the first embodiment of the present invention includes a light source unit 10 , a first collimator unit 20 , a flow cell unit 30 , and light detection units 40 , 50 .

[0032] The light source unit 10 irradiates light. In this case, the light source unit 10 includes a light emitting lamp 11 for irradiating light and a convex lens unit 13 for focusing the light irradiated by the light emitting lamp 11. As the light emitting lamp 11, an ultraviolet lamp for irradiating ultraviolet light (UV: Ultraviolet) in the wavelength range of 150nm to 450nm can be used.

[0033] The first collimator unit 20 collimates the light emitted from the light source unit 10 in parallel. Since the light is collimated in parallel by the first collimator unit 20, the light is incident in parallel to the flow cell unit 30. Of course, the first collimator unit 20 may also irradiate the light emitted from the light source unit 10 with slight refraction or in a manner that the wavelengths of the light are crossed according to the optical design.

[0034] The first collimator section 20 causes the light having a fixed angle, which has passed through the convex lens section 13 , to be irradiated in parallel to the inside of the flow cell section 30 .

[0035] The flow cell section 30 allows the flow medium to flow, and allows light to travel along the direction of travel of the flow medium while absorbing the wavelength of the flow medium. A flow chamber (not shown) is formed inside the flow cell section 30 for the flow of the flow medium. Light travels along the direction of travel of the flow medium in the flow cell section 30, thereby minimizing scattering and refraction caused by bubbles or dissolution when light passes through the flow medium, and reducing light loss. In addition, light can smoothly absorb the wavelength of the dissolution contained in the flow medium while passing through the flow medium, thereby improving light detection efficiency.

[0036] The flowing medium may be an etching solution used in semiconductor processes when manufacturing semiconductor wafers or photovoltaic cells, etc. As the etching solution, a phosphoric acid solution at 150° C. to 200° C. may be used. The flow cell portion 30 may be formed of a quartz material, a heat-resistant glass, or a polytetrafluoroethylene material that can prevent thermal deformation and corrosion in a high-temperature etching solution.

[0037] An inflow pipe portion 31 is connected to the lower portion of the flow cell portion 30 so that a flowing medium flows in, and an exhaust pipe portion 33 is formed on the upper side of the flow cell portion 30 so that the flowing medium flowing from the flow cell portion 30 is exhausted. At this time, light travels along the length direction of the flow cell portion 30. The inflow pipe portion 31 is connected to the lower portion of the flow cell portion 30, and the exhaust pipe portion 33 is connected to the upper side of the flow cell portion 30, so that the flowing medium flows from the lower side to the upper side of the flow cell portion 30. In addition, most of the bubbles contained in the flowing medium flow across the diameter of the flow cell portion 30 and then flow along the upper side of the flow cell portion 30, so that when the light flows along the inside of the flow cell portion 30, the light loss due to the bubbles can be minimized.

[0038] The flowing medium flowing in the flow cell section 30 is heated to 150° C. to 200° C. to suppress precipitation of substances contained in the flowing medium. In addition, the high-temperature flowing medium may flow in the flow cell section 30 so that the wavelength of the heated flowing medium is absorbed by light.

[0039] Therefore, it is not necessary to chemically treat the flowing medium several times to measure the concentration of the flowing medium under the conditions used in the actual semiconductor process and to increase the detection sensitivity of the flowing medium. In addition, it is not necessary to cool the flowing medium to room temperature, thereby preventing detection errors due to temperature differences in the flowing medium, and accurately predicting the state of the flowing medium under the conditions used in the actual semiconductor process. In addition, the matrix in the concentration analysis can be simplified, and the accuracy of the analyzed concentration can be improved.

[0040] The light detection units 40 and 50 detect the wavelength of light irradiated through the flow cell unit 30. The light detection units 40 and 50 can detect the wavelength of light transmitted through the flowing medium and absorbed, analyze the data sent by the light detection units 40 and 50, and measure the concentration of the eluted substance contained in the flowing medium.

[0041] The light detection sections 40 and 50 include a second collimator section 40 that focuses the light that has passed through the flow cell section 30 and a light detection cell section 50 that detects the wavelength of the light irradiated from the second collimator section 40 .

[0042] The second collimator unit 40 collects the parallel light emitted from the flow cell unit 30. The parallel light passes through the second collimator unit 40 and is collected, so that the detection efficiency of the light detection unit unit 50 can be improved.

[0043] The light detection unit 50 detects the wavelength of light irradiated from the second collimator unit 40. The light detection unit 50 can detect the wavelength absorbed by the flowing medium while transmitting the light, analyze the data sent by the light detection unit 50, and measure the concentration of the eluted substance contained in the flowing medium.

[0044] The light detection unit 50 may be a CCD (charge coupled device) module capable of simultaneously scanning a plurality of wavelengths. Therefore, the light detection unit 50 scans a plurality of wavelengths at a time, and thus the light detection time of the light detection unit 50 may be significantly shortened.

[0045] The flowing medium monitoring device further includes a noise reduction unit 51 installed on the light detection unit unit 50 to cool the light detection unit unit 50. The noise reduction unit 51 may be a cooling component or a cooling device that cools the light detection unit unit 50 to reduce the noise of the light detection unit unit 50. The noise reduction unit 51 suppresses overheating of the light detection unit unit 50, so that the noise of the detection signal is reduced.

[0046] The flow medium monitoring device also includes: a slit unit 53, which allows parallel light irradiated from the second collimator unit 40 to pass through and diffract (diffraction); a wavelength selection unit 55, which is arranged between the slit unit 53 and the light detection unit unit 50, and splits the light incident from the slit unit 53. As the wavelength selection unit 55, a grating that splits the light into multiple wavelengths can be applied. The grating splits the multiple wavelengths almost in parallel. The slit unit 53 and the wavelength selection unit 55 split the light into multiple wavelengths, so that multiple wavelengths are detected in the light detection unit unit 50 in a short time of about 5msec-10msec (milliseconds). Therefore, the scanning time of the light detection unit unit 50 is significantly shortened.

[0047] The flowing medium monitoring device further includes a first optical fiber portion 61, which is connected to the light source portion 10 and the first collimator portion 20, and the first optical fiber portion 61 forms an optical path so that the light irradiated from the light source portion 10 irradiates the first collimator portion 20. The first collimator portion 20 and the first optical fiber portion 61 are connected via a first optical fiber coupler 62.

[0048] The light source unit 10 can be installed at various positions regardless of the installation position of the flow cell unit 30 , thereby increasing the degree of freedom in installing the light source unit 10 and the flow cell unit 30 .

[0049] In addition, the first optical fiber portion 61 is connected to the light source portion 10 and the first collimator portion 20, so that the light source portion 10 can be installed separately from the flow cell portion 30. The high-temperature flowing medium of about 150°C-200°C passes through the flow cell portion 30, so that the flow cell portion 30 is heated by the high-temperature flowing medium. The light source portion 10 and the light detection unit portion 50 are installed separately from the flow cell portion 30 by the first optical fiber portion 61, so that the light source portion 10 can be prevented from being overheated due to the heat of the flow cell portion 30. In addition, there is no need to install an additional cooling device or insulation member in order to cool or insulate the light source portion 10.

[0050] The flow medium monitoring device further includes a second optical fiber portion 65, which forms an optical path so that the parallel light irradiated through the flow cell portion 30 is irradiated to the light detection unit portion 50. At this time, the second optical fiber portion 65 is connected to the second collimator portion 40 and the light detection unit portion 50, and the second collimator portion 40 is incident on the light passing through the flow cell portion 30. The second optical fiber portion 65 is connected through a second optical fiber coupler 66.

[0051] In addition, the second optical fiber portion 65 may be connected to the flow cell portion 30 and the light detection unit portion 50 .

[0052] The light detection unit section 50 can be installed at various positions regardless of the installation position of the flow cell section 30 , thereby increasing the degree of freedom in installing the light detection unit section 50 and the flow cell section 30 .

[0053] In addition, the second optical fiber portion 65 is connected to the light detection unit portion 50 and the second collimator portion 40, so that the light detection unit portion 50 can be installed separately from the flow pool portion 30. The high-temperature flowing medium of about 150°C-200°C passes through the flow pool portion 30, so that the flow pool portion 30 is heated by the high-temperature flowing medium. The light detection unit portion 50 is installed separately from the flow pool portion 30 by the second optical fiber portion 65, so that the light detection unit portion 50 can be prevented from being overheated due to the heat of the flow pool portion 30. In addition, there is no need to install an additional cooling device or insulation member in order to cool or insulate the light detection unit portion 50.

[0054] The flowing medium monitoring device can be installed with only one of the first optical fiber part 61 and the second optical fiber part 65, or with both the first optical fiber part 61 and the second optical fiber part 65. When the first optical fiber part 61 and the second optical fiber part 65 are installed on both sides of the flow cell part 30, it is not necessary to arrange the flow cell part 30, the light source part 10 and the light detection unit part 50 in a row, thereby increasing the installation freedom of the flowing medium monitoring device.

[0055] In addition, the first optical fiber unit 61 and the second optical fiber unit 65 may not be installed in the flowing medium monitoring device. In this case, the light source unit 10 and the flow cell unit 30 may be directly connected through the first collimator unit 20, and the light detection unit unit 50 and the flow cell unit 30 may be directly connected through the second collimator unit 40.

[0056] The second embodiment of the present invention is described below. The second embodiment is substantially the same as the first embodiment except for the light detection unit and the detection wavelength adjustment unit. Therefore, the same reference numerals are given to the same components as the first embodiment and their description is omitted.

[0057] Figure 2 FIG. 2 is a diagram showing the structure of a flowing medium monitoring device according to a second embodiment of the present invention.

[0058] Reference Figure 2, the flowing medium monitoring device of the second embodiment of the present invention further includes a detection wavelength adjustment unit 57, which adjusts the wavelength of light irradiated to the light detection unit 50 as the wavelength selection unit 55 is rotated. As the detection wavelength adjustment unit 57, a stepper motor unit (stepmotor) capable of rotating the wavelength selection unit 55 by 1 pitch at a time is proposed. Every time the wavelength selection unit 55 rotates by 1 pitch, a specific unit wavelength is sequentially irradiated to the light detection unit 50. The pitch angle of the detection wavelength adjustment unit 57 can be appropriately adjusted according to the range of the unit wavelength. If the detection wavelength adjustment unit 57 rotates by 1 pitch and irradiates the unit wavelength to the light detection unit 50 in sequence, the light detection unit 50 detects one of the multiple unit wavelengths each time and combines them. Therefore, multiple unit wavelengths can be combined to monitor the state of the concentration of the flowing medium, etc.

[0059] As the light detection unit 50, a photomultiplier tube (PMT component: Photomultiplier tube) that can sequentially detect the unit wavelengths irradiated from the wavelength selection unit 55 can be used. When a photomultiplier tube is used, the unit wavelengths are sequentially judged, so the detection sensitivity can be significantly increased. In addition, it is necessary to combine multiple unit wavelengths, so the analysis speed may be delayed.

[0060] The third embodiment of the present invention is substantially the same as the first embodiment except for the wavelength selection unit, so the same reference numerals are given to the same components as the first embodiment and their description is omitted.

[0061] Figure 3 FIG. 1 is a diagram showing the structure of a flowing medium monitoring device according to a third embodiment of the present invention.

[0062] If reference Figure 3 The flowing medium monitoring device of the third embodiment of the present invention further includes a wavelength selection unit 55, which is disposed between the light source unit 10 and the first collimator unit 20 and splits the light incident from the light source unit 10. At this time, the wavelength selection unit 55 is disposed between the first fiber coupler 62 and the convex lens unit 13 of the light source unit 10.

[0063] The wavelength selection section 55 selects a unit wavelength from the plurality of unit wavelengths irradiated by the light source section 10 and transmits it to the first optical fiber section 61. The unit wavelength passes through the first optical fiber section 61, the first collimator section 20, the flow cell section 30, the second collimator section 40 and the second optical fiber section 65 to reach the light detection unit 50. The above-mentioned unit wavelength is defined as a wavelength that absorbs the wavelength of one dissolution among the plurality of dissolutions contained in the flowing medium. The unit wavelength is irradiated to the flow cell section 30, and absorbs the wavelength of one dissolution in the flowing medium. Therefore, when the plurality of wavelengths absorb wavelengths in the plurality of types of dissolutions, the background phenomenon of spectral interference between the wavelengths can be prevented. Therefore, since the unit wavelength absorbs the wavelength only in the specific dissolution contained in the flowing medium, the concentration of the flowing medium can be detected more accurately.

[0064] The second convex lens 56 is disposed between the light detection unit 50 and the second fiber coupler 66. The second convex lens 56 focuses the light irradiated from the second fiber coupler 66 to the light detection unit 50. As a detection element, a photomultiplier tube (PMT) or an avalanche photodiode (APD) with improved sensitivity can be used.

[0065] The present invention is described with reference to the embodiments shown in the accompanying drawings, but these are merely examples, and a person skilled in the art will appreciate that various modifications and other equivalent embodiments may be derived therefrom.

[0066] Therefore, the true technical protection scope of the present invention should be determined according to the claims.

Claims

1. A flow medium monitoring device, characterized in that: include: a light source unit that radiates ultraviolet rays; a first collimator part, for collimating the ultraviolet rays emitted by the light source part; A flow cell portion for allowing a flow medium as an etching solution to flow, and for allowing ultraviolet rays to travel along a travel direction of the flow medium while absorbing a wavelength of the flow medium; as well as a light detection section for detecting the wavelength of ultraviolet rays passing through the flow cell section, The light detection unit comprises: a second collimator portion that focuses the ultraviolet light that has passed through the flow cell portion; and a light detection unit section, detecting the wavelength of ultraviolet rays passing through the second collimator section; The flow medium monitoring device also includes: a first optical fiber portion, the first optical fiber portion being connected to the light source portion and the first collimator portion, and the first optical fiber portion forming an optical path so that light irradiated from the light source portion is irradiated to the first collimator portion; and a second optical fiber portion, the second optical fiber portion forming an optical path so that the light irradiated through the flow cell portion is irradiated to the light detection unit portion, The light source unit comprises: a light emitting lamp that radiates light; and The convex lens part focuses the ultraviolet light emitted by the light emitting lamp. An inlet pipe is connected to the lower part of the flow pool to allow the flow medium to flow in, and an outlet pipe is formed on the upper side of the flow pool to allow the flow medium flowing from the flow pool to be discharged, wherein the ultraviolet rays travel along the length direction of the flow pool.

2. The flow medium monitoring device according to claim 1, characterized in that: The first collimator section makes the angle of the ultraviolet rays incident at a fixed angle from the light source section parallel.

3. The flow medium monitoring device according to claim 1, characterized in that: The second collimator portion focuses parallel ultraviolet rays that have passed through the flow cell portion onto the light detection unit portion.

4. The flow medium monitoring device according to claim 1, characterized in that: The invention further includes a noise reduction unit installed on the light detection unit to cool the light detection unit.

5. The flow medium monitoring device according to claim 1, characterized in that: Also includes: a slit portion that allows the ultraviolet rays irradiated from the second collimator portion to pass therethrough and causes the light to be diffracted; as well as The wavelength selection section is disposed between the slit section and the light detection unit section, and separates ultraviolet rays incident from the slit section to the light detection unit section.

6. The flow medium monitoring device according to claim 5, characterized in that: The light detecting unit further includes a detection wavelength adjusting unit that adjusts the wavelength of ultraviolet rays irradiated to the light detecting unit as the wavelength selecting unit is rotated.

7. The flow medium monitoring device according to claim 1, characterized in that: The device further includes a wavelength selection unit that is disposed between the light source unit and the first collimator unit and splits ultraviolet rays incident from the light source unit.

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